I used my Ultimaker to make a laser effect called "Laser Sky." The heart of the mechanism is a spinning multi-sided mirror. People often take apart laser printers to get such a mirror, but I was able to get pretty good results printing one from scratch.
Please enjoy a process video which includes concept, printing, wiring, programming, and assembly:
https://www.youtube.com/watch?v=https://youtu.be/vYmv8dOtOBA